The present invention relate to all observation window of a hyperbaric chamber, and more particularly to an observation window, which has a frame less likely to be deformed due to high temperature caused by solder welding, and which is constructed in such a manner as to provide the users with widened view angle.
Hyperbaric oxygen chambers have been provided to treat divers with the bends, a serious illness caused by ascending from deep water too fast. This treatment overcomes oxygen starvation in the tissues, by flooding the body""s fluids with life-giving oxygen. Hyperbaric oxygen treatment has many other applications now, including treatment of a variety of illnesses and revitalization of athletes.
Referring to FIGS. 4 and 5, a conventional observation window 2 of a hyperbaric chamber includes a frame 22, a transparent member 24, and a securing member 26 having a central hole 261. The frame 22 is secured to a holed portion 21 of the hyperbaric chamber by means of solder welding; the chamber is usually made of strengthened metal so that it can stand high air pressure inside. The frame 22 has a central observation hole 221, a holding room 23, and several bolt holes around the holding room 23. A first ringed leak-prevention pad 242 is disposed in the holding room 23. The transparent member 24 is fitted into the holding room 23. A second ringed leak-prevention pad 241 is disposed on the transparent member 24. And, the securing member 26 is disposed on the outer side of the transparent member 24, and is joined to the frame 22 with bolts 25 screwed through connecting holes thereof as well as the bolt holes of the frame 22. Thus, the transparent member 24 is secured to the frame 22 without possibility of falling off, and the pads 241, 242 are tightly pressed against it to prevent leakage of gas through the joints.
Thus, the persons delivering the service with the chamber can observe the customers who are sitting in the chamber with hyberbaric oxygen provided therein. However, the observation window is found to have disadvantages as followings:
1. Annular slopes are usually formed around the outer side of die frame 22 and around the hole of the chamber so that a relatively big space is formed between the frame 22 and the chamber. So, solder can be added to the space in more amount when solder welding is used to join the frame 22 and the chamber together. Consequently, the welding process would take relatively long time, and produce a lot of heat that would cause deformation of the frame 22 that will hinder the tight connection of the transparent member 24 to the holding room 23, and make leakage likely to happen.
2. The securing member 26 will cause the view angle of the observation window to become smaller, hindering proper observation of the customers.
Therefore, it is a main object of the present invention to provide an observation window which has a frame less likely to be deformed due to high temperature caused by solder welding.
It is another object of the present invention to provide an observation window which is constricted in such a manner as to provide the users with widener view angle.
The observation window includes a frame, and a transparent member. The frame is fixedly joined to the chamber wall. The frame includes an outer annular connecting portion, and an inner annular holding portion that defines a central observation hole, and defines an annular space with the connecting portion. The annular space helps reduce effects of deformation of the connecting portion on the holding portion that is caused by high temperature of solder welding used to join the frame to the chamber wall. An O-shaped ring is fitted between the transparent member and the holding portion to prevent the transparent member from falling off the frame instead the conventional securing member that will narrow the view angle.